If you are worried about elevation I wouldn't recommend going to the western slope. I'm pretty sure there is not a pass under 10,000 feet unless you drop down into New Mexico and then come up.
Someone posted about Mueller SP and I would recommend it if you want to be close to the front range area of Colorado Springs. Most of the sites have no hookups but there are quite a few with electric only.
Many things to do and see in the area, though you might want to make reservations early as the park is pretty full during the fall colors.
Cripple Creek has casinos if you are into that but a historic mining town none the less. Victor, though no casinos, also has a rich history. Woodland Park has a number of restaurants and beautiful views of Pikes Peak. Pikes Peak, of course. You can either drive up or take the railroad out of Manitou Springs. Colorado Springs has many attractions and is not that far of a drive.
If you want full hookups the is the tiny little town of Lake George that has a couple of RV parks, though far from the "resort" types. They cost less than Mueller, though, and are just a close to everything.
If you want to try some fishing there is Eleven Mile, which is also a state park with camping available, again most sites no hookups but more than enough with electric. Spinny Reservoir is not too far from Eleven Mile.
The western slope has much to offer yet so does the area between the front range and the Continental Divide.
I'm guessing by now you are figuring out there is ALOT to see in the state and I can tell you that a month is not nearly enough time to see it all. I would suggest to pick an "area" of the state, set up a base camp and then explore to your hearts content.
BTW, I hate going to Denver and only go there to visit family or to DIA. I try to stay away from Colorado Springs as much as I can but have to go there now and then for doctors and such, plus visiting family. There's a reason we chose to live where we do. Far enough out from the front range to not have to put up with it but close enough when we need it!